Fade protector

Abstract

A light curable anti-glare coating liquid composition for coating onto a transparent substrate, the composition comprising a dispersion of nanoparticles of a mineral oxide suspended in a mixture of an acrylate-functional resin that is compatible with the nanoparticle dispersion, compatible solvent, incompatible solvent that has a lower volatility than the compatible solvent, and a surfactant that has poor or limited compatibility with the dispersion.

Description

CROSS REFERENCE TO RELATED APPLICATIONS [0001] This is a division of my copending U.S. patent applicaion Ser. No. 10 / 389,083 filed Mar. 15, 2003 for which benefit is claimed under 35 U.S.C.§120.FIELD OF THE INVENTION [0002] This invention relates to a fade protector which is for use in a glazed frame to protect documents of pictures displayed in the frame from fading caused by exposure to light, and to an anti-glare coating which is particularly useful for a fade protector. BACKGROUND OF THE INVENTION [0003] The protection of framed documents or pictures from the ravages of light typically involves the use of conservation glass which is expensive. More recently the present assignee has introduced a Do-it-yourself (DIY) framing film that blocks out harmful UV radiation. Such films reduce fading and control glare when applied to the glass in picture frames. The film comprises a TJV absorbing PET (polyethylene terephthalate) layer about 4 mil (0.1 mm) thick having an antiglare hard coa...

AI Technical Summary

Benefits of technology

[0013] The anti glare hard coating is preferably a UV cured acrylate resin coating having a nanoparticle dispersion therein which has a 60 degree gloss of 80-100 gloss units and preferably 85-95 gloss units, a haze of less than 12% and preferably 9-11% and scratch resistance to 0000 steel wool. The anti glare coating has a surface structure that scatters light so as to reduce unwanted reflection but the bulk of the coating is clear with low or no haze so that the image of the picture or document does not suffer from excessive “greying out” or loss of contrast. The coating is about 4 microns in thickness.

[0014] The other surface of the polymeric film (away from the anti-glare hard coat) may be masked by a release liner which protects the film against scratching or marking prior to use and is-also low tack and easily peelable from the film. If the removal of the film causes a build up in static electricity on the film which attracts dirt, dust etc. then the tacky liner may be used as a cleaner to remove the dirt particles from the newly exposed surface on the film and / or the glazing surface. The release liner preferably comprises a polyethylene coated paper.

[0018] Yet still another invention provides a method of protecting a glazed frame mounted document from the ravages of light using a fade protector comprising a transparent UV absorbing polymeric film layer having a thickness such that the film in use remains substantially flat against the gluing when clamped between the frame and glazing, the polymeric film being coated on its exposed side in use with a transparent anti-glare hard coating and its other side is masked by a release liner which is low tack and easily peelable from the film, wherein in said method the glazing is removed from the glazed frame, the mask is removed from the film and its tacky surface is used to clean the surface(s) of either the glazing or film, the glazing then being re-assembled in the frame with the fade protector clamped adjacent the external surface of the glazing with the anti-glare coating facing outwardly.

[0021] By suitable choice of compatible and incompatible solvents and their relative volatility and-suitable method of preparation it is possible to prepare coatings that are stable solutions / dispersions prior to application but that undergo a limited and controlled destabilization of the nanoparticle dispersion at the surface of the coating together with a concentrating of the surfactant during oven drying and / or UV curing such that a structure and roughness is produced in the surface region of the coating that scatters light while the bulk of the coating forms a film in which the dispersion remains stable and so remains clear, transparent and with low or no haze. This scattering results in lower specular reflection and higher diffuse reflection and so reduces measured gloss and reduces unwanted glare and reflection. The structure also scatters light in transmission and so measured haze is lower than for a film without the surface structure because the scattering effect is confined to the surface the net haze increase is less than for a conventional anti-glare coating in which the particles are dispersed evenly throughout the coating.

[0022] An anti-glare coating according to the present invention may be tailored to achieve varying level of gloss and haze by concentration of nanoparticles and by choice of resins, solvents, and surfactant in such a way that the roughness and thickness of the surface layer changes but the haze and scatter still remain a surface effect.

Problems solved by technology

The protection of framed documents or pictures from the ravages of light typically involves the use of conservation glass which is expensive.

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